Some conventional probes use electromagnetic induction to non-destructively inspect a metallic part for anomalies. Conventional probes use induction coils to generate and direct magnetic fields into the metallic part. The magnetic fields cause eddy currents to form in the metallic part, which induces a return magnetic field out of the part. The return magnetic field is detected by the probe and analyzed to determine whether anomalies are present in the part.
Inspection of thicker metallic parts uses magnetic fields at a lower frequency. However, magnetic fields at lower frequencies tend to decrease the signal-to-noise ratio of the probe, which reduces the sensitivity and accuracy of the probe.